Control device



March 14, 1939. K EGGLESTON 2,150,858

, CONTROL DEVI CE Fi led May 5, 1937 1/3 "a ma INVENTOR W K. W-

BY W M V6 ,A..; A TTORNEY Patented Mar. 14, 1939 PATENT OFFICE CONTROL DEVICE Gilbert K. Eggleston, Detroit, Mich., assignor to Detroit Lubricator Company, Detroit, Mich., a corporation of Michigan Application May 3, 1937, Serial No. 140,431

9 Claims.

My invention. relates generally to controls and more particularly to temperature responsive controls.

One of the objects of my'invention is to provide a new and improved temperature responsive control of the type employing fusible material for releasably holding an actuator against operation at temperatures below a predetermined temperature.

Another object of my invention is to provide a new and improved control of the above mentioned character which may be reset without the necessity of replacing the fusible material.

Another object of my invention is to provide a new and improved control having provisions for displacing the fusible material on predetermined liquidity thereof to permit actuation of a control.

The invention consists in the improved construction and combination of parts, to be more fully described hereinafter and the novelty of which will be particularly pointed out and distinctly claimed.

In the accompanying drawing, to be taken as a part of this specification, I have fully and clearly illustrated my invention, in which d'rawing- Figure 1 is a side view shown partly in elevation and partly in section of a control device embodying my invention;

Fig. 2 is an end view of the control device taken in the direction of the arrows 2-2 of Fig. 1 showing the relative positions of certain of the parts of the device when the device is set for operation;

Fig. 3 is a View shown. in cross section taken along the line 3-3 of Fig. 1 of certain other parts of the device showing the relative positions thereof and which positions correspond to the positions of the parts shown in Fig. 2;

Figs. i and 5 are views similar to the views of Figs. 2 and 3, respectively, showing the positions that the parts of the device will assume after operation of the device;

Figs. 6 and *7 are views similar to the views of Figs. 4 and 5, respectively, showing the device reset and the relative positions that the parts will assume, and

Fig. 8 is a view of certain of the parts of the device in perspective to show the structural details thereof.

Referring to the drawing by characters of reference, the device shown includes a supporting member I, preferably a hollow casing, one wall of which may be formed by a movable closure member or cover 2. Supported by the casing I. externally thereof, there may be a tubular extension member or casing 3 that may be rigidly secured at one of its ends to the casing I, the extension tube preferably being secured to and pro- J'ecting from the casing wall that is opposite the cover 2. Adjacent its free or outer end the extension member '3 is preferably provided with a chamber 4 that may be closed by a closure plug 5 that may screw thread into the outer end of the extension member 3. The chamber 4 is preferably cylindrical, or in the form of a bore, having its axis extending longitudinally of the extension member 3, and-disposed in. the cylindrical chamber 4 there is a movable fluid displacement member, preferably in the form of a rotor 6. The rotor'B preferably has an aperture longitudinally therethrough for receiving an end portion of a shaft 7 that rotates with the rotor B and extends therefrom longitudinally through the extension member 3 and projects into the casing I. The rotor 6 and the shaft 1 may be secured together by pins l or these parts may be secured together in any other suitable manner.

The rotor 6 has a rotatable sliding fit with its cylindrical chamber 4 but does not completely fill the chamber, the" rotor 6 having a recess or cutout that is preferably defined by angularly or radially disposed wall surfaces 8, 9 that extend longitudinally and preferably coextensive of the rotor B. In the present instance, the angularly disposed wall surfaces 8, 9 are spaced slightly more than 90 apart, but it will be understood that the angle between these wall surfaces may be selected as desired. The wall surfaces 8, 9 cooperate with the inner wall surface of the extension member 3 to provide an enclosed space or well for fusible material I0 which may be solder, or any other suitable material. Partly surrounding the shaft 1 the rotor 6 has a wall portion I I that joins the wall surfaces 8, 9, and this wall portion I l is preferably rounded, as shown. The fusible material it] is adapted to hold the rotor 6 against rotation in its chamber 4 at temperatures of the fusible material below a predetermined temperature, or at temperatures below the temperature at which the material will liquify and flow. Projecting into the well there is a dam [2 over which the fusible material l0 flows when the fusible material becomes sufiiciently liquified to permit rotation of the rotor which, as will later be seen, is biased to rotate. The dam 12 may be an integral, extended wall portion of the side wall of the extension tube 3 and it preferably projects radially therefrom toward the axis of the rotor 6. The dam. I2 preferably has side wall surfaces 13 and 14 extending longitudinally of and coextensive with the well, and these wall surfaces are preferably angularly disposed and converge inwardly from the side wall of the extension tube 3 toward the axis of the rotor 6. The dam l2 has an overflow portion l5 which is preferably rounded to reduce resistance to flow thereover, and this overflow portion I5 is spaced from the wall portion II to provide a flow restricting pas-v sage or space "5 for'flow of the fusible material 7 thereof.

from one side of the dam to the other side to prevent rotation of'the; rotor 6, need not ad hereto the inner wall surface of the extension tube 3 for when the fusiblematerial is in a solid state, or substantially so, the dam 'I 2will prevent it from moving. When the fusible material l0 becomes liquified,the rotor 6 rotates and pushes the fusible material over the dam l2 to the other side thereof where the rotor recess forms the well to receive the fusible material; It will thus be seen that the chamber 4 has relatively movable walls and hasa flowrestricting' passage for'flow of the ffusible material on predetermined degrees of liquidity thereof. V I e 'Mounted'within the casing I there is a control, designated. in general by the numeral l8, which may be a switch having an operating arm or lever I9. Within the casing I andfreely mounted on the shaft I there is azlever member 28, preferably in the form of a wheel or platelike disc. The plate'28 preferably has a cam,

' and to this end the'plate may be provided off 22 defining the slotted aperture.

'ture'2l in sliding engagement with the cam surface 22, and the cam and switch arm l9'may be arranged so that when the plate 20 is; in a position such that the switch arm is midway between the ends of the slot 2|, as shown in Figs. 2 and 6," the switch I8 will be in closed position. When the plate-20 is rotated in either direction the cam will pivot switch; arm l9 upward to open the switch I8.

Rigidly secured on the shaft! within the hasing I there is preferably an arm 25 that extends laterally from the shaft. Carried by the, arm

25 and rigidly secured thereto, adjacent its outerend, there is a pin 26 that projects into an elongated, slotted aperture 2'! in; the plate 20. A

- helical coil spring- 28 is provided and acts to rotate the lever or 'plate 20, and in so doing acts to rotate the shaft 1. The'spring 28 may be under tension having. one end attached to the plate 20 adjacent the outer periphery thereof and having its otherend attached to the casing l. A'pair of opposite side walls of the casing l maybe provided with recesses 29, 30, one in each wall, and in one or the other of these,

recessespdepending upon the positions'of the parts of the device, the anchored end of the spring 28 is held against movement. When the anchored'end of ,thespring 28 is held in the recess 29, the spring holds the plate 28 at one end of its recess 21, againstpin 26 ,of the arm 25, and acts to rotate the plate 28in 'a counterclockwise direction, as seen in Fig. 2. 'When the anchored end of spring 28 is held againstmove The fusible material I0, when serving ment in the recess 38, the spring will hold the plate 20 at the other end of itsrecess 21 in.

. engagement with the pin 26 of arm 25, and will direction,

act to rotate plate 20 in 'a clockwise as seen in Fig. 6.

vThe operation of the'herein-described device is as follows: The device may be employed, among other uses, for controlling the circuit of 'a heating apparatus control (not shown) to decrease or stop heatinput to a boiler (not shown) .when the temperature of the boiler becomes dan- "gerou'sly high. When the device is employed for the above mentioned purpose the extension tube 3 is preferably inserted. into the boiler with the fusible material In in good heat transferrelatemperature the fusible material will liquify which will permit the spring 28, acting through the plate 20,'arm 25 and shaft 1, to rotate the rotor 6 in a counterclockwise direction, as seen in Fig. 2. As the rotor 6 is rotated by the spring 28, the liquid fusible material I0 is displaced by the rotor 6 and is pushed ahead of the wall 8 thereof and forced to fiowover the dam overflow l5 until substantially all of the fusible material is on the other side of the dam. The spring 28, through rotation of the rotor 6, forces the fusible material II) from one side of the dam [2, through the flow restricting passage or outlet I6 to the other side thereof, on predetermined liquidity of the fusible material, and the rotor 6 forms the well on the said other side of the dam for receiving the fusible material. Also, as the plate 20 is rotated in a counterclockwise direction as seen in Fig. 2, its. carhpivotsthe switch arm I8 to closed circuit position. In the present instance, the switch arm -l9 when moved to open position serves as 'a stop to limit rotation of the rotor 6,. but it will be appreciated that other means may be provided to limit rotation of the rotor 6. Preferably the rotor 6 is stopped at a position such thatthere will be some fusible material left'between the rotor wall 8 and the dam wall [3, as shown in Figs. '5 and 7. The parts of the device now assume the positions shown in Figs. 4 and 5. After a short time the fusible material H1 will harden in the position;

shown in Fig. 5, and will thus prevent movement of the rotor 6 in a clockwise direction. By reason of the slot 21 in the plate 20, and the pin 26 of arm 25 operating in the slot 21, it will be seen that a lost motion connection is provided which permits rotation of plate 20' to close switch l8 after the fusible material hashardened. To reset the device the anchored end of position shown in Fig. 6, which moves theswitch arm l9 downward to its closed circuit position. When the fusible material Ill again fuses, the spring28 will rotatethe plate 28 in a clockwise direction, as seen in Fig. 6, and move the switch arm is to'closed position. -As this isgoccurring the fusible material is forced back over the dam overflow I5to the position shown in Fig. 3, and after the fusible material has hardenedQthe device can again be set by anchoring the outer or readily detachable end of the spring. 28 in the recess of casing I.

spring 28 is detached and anchored to the cas-" It will now be seen that I have provided a new and improved temperature responsive control having a fuse, and one which canbe readily reset without the necessity of replacing the fuse. It will also be seen that by reason of the dam in my device, the fusible material will not need to adhere to the wall of its well to prevent operation of the device, for the dam will prevent movement of the fusible material until such time as the fusible material becomes sufficiently liquefied to flow over the dam.

What I claim and desire to secure by Letters Patent of the United States is:

1. In a control device, a body member having a recess with spaced end walls, a second body member closing an open side of said recess and having a wall member rigid therewith and extending into said recess in spaced opposing and overlapping relation to one of said end walls, fusible material confined in and substantially filling said recess, operating means to move one of said body members relative to the other of said body members so that the space between said wall member and said one end wall will be decreased, said fusible material when solid blocking movement of said wall member and opposing operation of said means, and means for flow of said fusible material out of blocking position and from and to the opposite sides of said wall member.

2. In a control device, a body member having a recess with spaced end walls, a second body member closing an open side of said recess and having a wall member rigid therewith and extending into said recess inv spaced opposing and overlapping relation to one of said end walls, fusible material confined in and substantially filling said recess, adjustable operating means to reciprocate one of said body members relative to the other of said body members so that the space between said wall member and said one end wall will be decreased and increased alternately, said fusible material when solid blocking movement of said wall member and opposing operation of said means, and means for flow of said fusible material out of blocking position and from and to the opposite sides of said Wall member, and means to adjust said operating means to reverse the effective direction of force thereof on said one body member.

3. In a control device, a pair of relatively rotatable body members, said members being generally cylindrical and fitted one within the other, one of said members having a longitudinal recess providing opposed walls, the other of said members having a wall member extending into said recess in opposed relation to said walls, fusible material in and substantially filling said recess, means confining said material in said recess, means for flow of said material from and to opposite sides of said wall member, and means operable upon melting of said material torotate one of said body members relative to other of said body members.

4. In a resettable control device, a pair of body members, one of said members having a recess, the other of said members closing said recess and having a wall projecting into said recess, said wall having a peripheral portion spaced from a portion of the recess wall to provide a passageway, fusible material filling said recess and transferable through said passageway upon fusion by movement of one of said members relative to the other of said members, a spring having one end anchored to the movable one of said members and having its other end shiftable to change the direction of force of the spring on said movable member, and control means operable upon movement of the movable one of said members, said spring acting upon fusion of said material to move the movable one of said members as the fused material is forced by the spring through said passageway.

5. In a control device, a housing member having a cylindrical chamber, means closing the ends of said chamber, a body member substantially of equal length with and rotatable in said chamber and having a curved surface fitting the curved chamber wall, said body member having a longitudinal recess, a wall member projecting from said housing member into said recess, said wall member and said recess having substantially equal radial cross-sectional areas, means to rotate said body member, and fusible material in said recess, said material when solid opposing movement of said body member, said wall member having an edge portion spaced from the wall of said recess for flow of said fusible material from and to opposite sides of said wall member.

6. In a control device, supporting means, a reciprocally rotatable shaft carried by said means, an arm fixed on said shaft, a plate member journaled on said shaft and having a slot, a projection on said arm cooperable with the end walls of said slot to hold said plate member against rotation, said plate member having a cam slot of substantially twice the length of said firstnamed slot, said cam slot having duplicate operating portions extending oppositely from its midpoint, a coil spring having one end anchored to said plate member and having its opposite end movable to position the spring on opposite sides of the center of said plate member, a control means, an operating member for said control means and having a cam follower member extending into said cam slot, a casing having a chamber receiving a portion of said shaft, and fusible material confined in said chamber and holding said shaft against rotation.

7. In a control device, a movable control means having an initial position, operating means having an initial position and acting upon movement therefrom in different directions to move said control means from its said initial position, said operating means acting upon return movement to its initial position to move said control means to its initial position, a spring having one end anchored to said operating means and having its other end shiftable, said spring acting when its other end is in one position to move said operating means in one direction and acting when its other end is in another position to move said operating means in another direction, a releasable member having two positions and acting in each of said two positions to oppose movement of said operating means beyond its initial'position by said spring, and fusible material operable to hold said releasable member alternately in each of its said two positions, said releasable member being alternately movable from and to its said two positions by said spring upon fusion of said fusible material.

8. In a control device, a movable control means, drive mechanism movable in opposite directions, said mechanism having means operable on movement of said mechanism in one direction to move said control means in one direction and having means operable on movement of said V mechanism in the opposite direction to move said gageable with said follower member and operable direction, and automatically releasable means opposing said shiftable means and holding said drive mechanism against movement;

9." Ina control device, a control means having 7 operative action upon movement in one direction,

a reciprocally movable means, a cam follower member, a cam member having cam surfaces ento move said follower member in a single direction upon opposite directions 'of'movement of said cam member, one of said members being carried by one of said means and theother of said members being carried by the other of said means, shiftable means operable-in one position to urge said movable means in one direction and operable in another position to urge said movable means in'the opposite direction, and automaticallyreleasable' means operable to oppose movement of said movable means. V

- K.QEGGLESTON.-

GILBERT 

